Xml comment check
In C#/VBNet there is a nifty thing called Xml comments. I always use it to explain my methods and classes. A good thing about Xml comments is that they pop up as intellisense. Press ctrl-J in Visual studio at your method call and your comments are shown. The comments survive project boundaries so your well crafted comments in the business layer pop up at the presentation method calls to aid the GUI programmers.
The comments don’t travel C#->VBNet though.
In VBNet you get squiggly lines when the method call and the Xml comment don’t match. In C# you have to go through the Analyze->Run code analysis to get the differences.